Heat pump

ABSTRACT

A heat pump includes a refrigerant circuit for a refrigerant, a refrigerant collector belonging to the refrigerant circuit and through which the refrigerant flows, an expansion device through which the refrigerant flows and connected downstream of the refrigerant collector as seen in the flow direction of the refrigerant, an evaporator belonging to the refrigerant circuit and through which the refrigerant flows and connected downstream of the expansion device as seen in the flow direction of the refrigerant, and a condensate pan that is assigned to the evaporator and is designed to catch condensate forming on the evaporator. The refrigerant collector is designed to be connected in a thermally conductive manner to the condensate pan. In order for heat present externally at the refrigerant collector to be transferred by thermal conduction to the condensate pan, a distance between the refrigerant collector and the condensate pan is at most 15 cm.

The invention relates to a heat pump according to the generic term ofclaim 1.

A heat pump of the type mentioned above is known from patent document EP3 358 277 A1. In the broadest possible sense, a refrigerant collectorprovided there is designed to be connected in a thermally conductivemanner to a condensate pan provided there by means of a pipe.

Another heat pump of a similar type is known from patent document EP 2500 676 B1. This consists of a refrigerant circuit for a refrigerant, arefrigerant collector that belongs to the refrigerant circuit andthrough which the refrigerant flows and an expansion device that belongsto the refrigerant circuit and through which the refrigerant flows andwhich is connected downstream of the refrigerant collector as seen inthe flow direction of the refrigerant, an evaporator that belongs to therefrigerant circuit and through which the refrigerant flows and which isconnected downstream of the expansion device as seen in the flowdirection of the refrigerant, and a condensate pan that is assigned tothe evaporator and is designed to catch condensate forming on theevaporator. In the case of this solution, a heat exchanger is arrangedin the condensate pan to keep it ice-free. Refrigerant flows throughthis, which is then supplied to the evaporator itself.

The object of the invention is to improve a heat pump of the typementioned above. In particular, the efficiency of the heat pump is to beincreased.

This object is achieved with a heat pump of the type mentioned above bymeans of the features listed in the characterizing portion of claim 1.

According to the invention, it is therefore provided that, in order totransfer heat present externally on the refrigerant collector by thermalconduction from the outside to the condensate pan, a distance betweenthe refrigerant collector and the condensate pan is at most 15 cm.

In other words, the solution according to the invention is thuscharacterized in that forming heat, in particular, on an external wallof the refrigerant collector is transferred to the condensate pan bythermal conduction. In the aforementioned prior art, on the other hand,the heat transfer takes place in the broadest sense, in particular,either to a very small foreseeable extent via said pipeline (EP 3 358277 A1) or by convection (EP 2 500 676 B1), namely by the fact thatcontinuously new hot refrigerant is conveyed to the condensate tank viaa pipeline and the said heat exchanger, i.e., the heat is transported inan extra manner to the condensate tank by means of the refrigerant.However, in the case of the solution according to the invention, asalready explained, the heat present on the outside of the refrigerantcollector is transferred, in particular, by thermal conduction (andwhere applicable, also via heat radiation) to the condensate pan in anycase, which increases the efficiency of the heat pump accordingly. Therequirement that the refrigerant collector be designed to be connectedto the condensate pan comprises in a thermally conductive manner, on theone hand, the option that this (i.e., the refrigerant collector) isarranged directly on the condensate pan, i.e., directly in contacttherewith, but, on the other hand, it can also be provided that, betweenthe refrigerant collector and the condensate pan, a heat conductor isarranged, which conducts the heat from the refrigerant collector to thecondensate pan.

Other favourable further embodiments of the heat pump according to theinvention result from the dependent patent claims.

The heat pump according to the invention including its favourablefurther embodiments according to the dependent claims is explained inmore detail below on the basis of the graphic illustration of twoexemplary embodiments.

THE FIGURES SHOW

FIG. 1 schematically, a first embodiment of the heat pump according tothe invention, in which the refrigerant collector and the condensate panare designed to be directly connected to each other; and

FIG. 2 schematically, a second embodiment of the heat pump according tothe invention, in which the refrigerant collector and the condensate panare designed to be connected to each other via a thermally conductiveelement.

The present invention, shown in FIGS. 1 and 2 , relates to a heat pump.This consists of a refrigerant circuit 1 for a refrigerant, arefrigerant collector 2 that belongs to the refrigerant circuit 1 andthrough which the refrigerant flows and an expansion device 3 thatbelongs to the refrigerant circuit 1 and through which the refrigerantflows and which is connected downstream of the refrigerant collector 2as seen in the flow direction of the refrigerant, an evaporator 4 thatbelongs to the refrigerant circuit 1 and through which the refrigerantflows and which is connected downstream of the expansion device 3 asseen in the flow direction of the refrigerant, and a condensate pan 5assigned to the evaporator to catch condensate forming on the evaporator4.

Furthermore, it is provided that the refrigerant collector 2 isconnected to the condensate pan 5 in a thermally conductive manner. Inparticular, it is preferably provided that refrigerant collector 2 isdesigned to be connected to the condensate pan 5 in a “convection-free”manner. It is further preferred that the thermal conductive element 6 isdesigned to be contact-free from the refrigerant. This means that, forexample, in particular, a pipeline conveying the refrigerant is not usedas a thermal conducting element 6, but a separate heat conductionelement 6 is provided for heat conduction.

An electric heating device, which is possibly provided on the condensatepan to keep it free of ice, as can be seen, can be dispensed with thanksto the solution according to the invention, which solution ultimatelyincreases the efficiency of the heat pump.

For the heat pump according to the invention, it is essential that adistance between the refrigerant collector 2 and the condensate pan 5 isat most 15 cm, preferably less than 10 cm, more preferably less than 5cm, or even (only) 0 cm. The latter case is shown in FIG. 1 , i.e., inthis solution. it is provided that the refrigerant collector 2 and thecondensate pan 5 are designed to be in contact with one another. As analternative, it is preferred that, a preferably metallic thermallyconductive element 6 (because it conducts heat well) is arranged betweenthe refrigerant collector 2 and the condensate pan 5, see FIG. 2 . Therequirement according to the invention regarding “15 cm at most” isbased on the pragmatic consideration that, at a significantly largerdistance (such as both EP 3 358 277 A1) mentioned at the beginning, norelevant heat transfer can be achieved for the intended purpose anymore.

Furthermore, the refrigerant collector 2 is preferably arranged belowthe condensate pan 5 when the heat pump is operated as intended. It isalso preferred that the condensate pan 5 comprises a drainage channeland/or that the refrigerant collector 2 is at least connected to thedrainage channel in a thermally conductive manner.

In addition, it is preferred that the refrigerant collector 2 isdesigned as a high-pressure collector. In this case, the refrigerantcircuit 1 preferably comprises a high-pressure side 1.1 with thecondenser 8 and a low-pressure side 1.2 with the evaporator 4.Furthermore, it is preferred that the refrigerant collector 2 isarranged on the high-pressure side 1.1 of the refrigerant circuit 1.This causes the refrigerant in the refrigerant collector 2 and thus therefrigerant collector 2 itself to have a relatively high temperature.Thus, a lot of heat energy can be transferred to the condensate pan 5 tothaw it.

Furthermore, it is preferred that the refrigerant circuit 1 comprises acompressor 7 through which the refrigerant flows and which is downstreamof the evaporator 4 as seen in the flow direction of the refrigerant.Ultimately, it is preferred that the refrigerant circuit 1 comprises acondenser 8 through which the refrigerant flows and which is downstreamof the compressor 7 as seen in the flow direction of the refrigerant.

The heat pump according to the invention according to the exemplaryembodiment in FIG. 1 works as follows (FIG. 2 is analogous accordingly):

During regular operation of the heat pump, a condensate forms on therelatively cool evaporator 4, which drips down from it and is collectedby the condensate pan 5. Since the condensate itself is cold, it mayoccur that the condensate pan 5 ices and the condensate can no longerescape properly from the condensate pan 5 via a drain. In the heat pumpaccording to the invention in accordance with the exemplary embodimentfrom FIG. 1 , the refrigerant collector 2 is now arranged directly underthe condensate pan 5. In this refrigerant collector 2, there is warmrefrigerant, which heats the refrigerant collector 2. Since therefrigerant collector 2 is in direct contact with the condensate pan 5(or in accordance with FIG. 2 , is connected to this via the thermallyconductive element 6), it transfers part of its heat energy to this,whereby the ice located in it is defrosted or thawed, or can not form atall during ongoing operation of the heat pump. Thereby, the heat pumpaccording to the invention prevents the condensate pan 5 from freezingin a simple and efficient manner, which in turn, improves the efficiencyof the heat pump itself.

REFERENCE LIST

-   -   1 refrigerant circuit    -   1.1 high-pressure side    -   1.2 low-pressure side    -   2 refrigerant collectors    -   3 expansion device    -   4 evaporator    -   5 condensate pan    -   6 thermally conductive element    -   7 compressor    -   8 condenser

1: A heat pump comprising a refrigerant circuit (1) for a refrigerant, arefrigerant collector (2) that belongs to the refrigerant circuit (1)and through which the refrigerant flows, an expansion device (3) thatbelongs to the refrigerant circuit (1) and through which the refrigerantflows and which is connected downstream of the refrigerant collector (2)as seen in the flow direction of the refrigerant, an evaporator (4) thatbelongs to the refrigerant circuit (1) and through which the refrigerantflows and which is connected downstream of the expansion device (3) asseen in the flow direction of the refrigerant, and a condensate pan (5)assigned to the evaporator (4) to catch condensate forming on theevaporator (4), wherein the refrigerant collector (2) is designed to beconnected in a thermally conductive manner to the condensate pan (5),wherein, in order to transfer heat present externally on the refrigerantcollector (2) to the condensate pan by thermal conduction, a distancebetween the refrigerant collector (2) and the condensate pan (5) is atmost 15 cm. 2: The heat pump according to claim 1, wherein a distancebetween the refrigerant collector (2) and the condensate pan (5) is lessthan 10 cm, more preferably less than 5 cm, or 0 cm. 3: The heat pumpaccording to claim 1, wherein a thermal conductive element (6) isarranged between the refrigerant collector (2) and the condensate pan(5). 4: The heat pump according to claim 3, wherein the thermalconductive element (6) is designed to be contact-free from therefrigerant. 5: The heat pump according to claim 1, wherein therefrigerant collector (2) is located below the condensate pan (5) whenthe heat pump is operated as intended. 6: The heat pump according toclaim 1, wherein the condensate pan (5) comprises a drainage channel,wherein the refrigerant collector (2) is at least designed to beconnected to the drainage channel in a thermally conductive manner. 7:The heat pump according to claim 1, wherein the refrigerant collector(2) is designed as a high-pressure collector. 8: The heat pump accordingto claim 1, wherein the refrigerant circuit (1) comprises ahigh-pressure side (1.1) and a low-pressure side (1.2), wherein therefrigerant collector (2) is located on the high-pressure side (1.1) ofthe refrigerant circuit (1). 9: The heat pump according to claim 1,wherein the refrigerant circuit (1) comprises a compressor (7) throughwhich the refrigerant flows and which is downstream of the evaporator(4) as seen in the flow direction of the refrigerant. 10: The heat pumpaccording to claim 9, wherein the refrigerant circuit (1) comprises acondenser (8) through which the refrigerant flows and which isdownstream of the compressor (7) as seen in the flow direction of therefrigerant.